Construction of spring wheels



lMay 13 1924.

F. BRATT CONSTRUCTION OF SPRING WHELS 2 Sheets-Sheet l Filed April 18 A)922 Il Q May 13, 1924. F. ERATT CONSTRUCTION OE SPRING WHEELS FiledApril 18 1922 2 Sheets-Sheet 2 da@ ffm@ 47. WW L@ Patented May 13, 1924.

UNITED srarss Pr `FRANCIS BRATT, oF ILADYWo'on, BIRMINGHAM, ENGLAND.)

CONSTRUCTIONOF SPRING WHEELS. l

` .Application ined April 1e, 1922'. serial 110.555,370;

new and useful Construction of Springv lVheels, of which the followingis a specification.

This inventioncomprises certain improvementsL in or relating to theconstruction of s rin@ or shock-absorbin wheels such as are used forexample as the road wheels of cars7 lorries, cycles, and other roadvehicles, either motor-driven or otherwise, or as the landing wheels ofaeroplanes and other laircraft, or for other like purposes.

The obj ect is to provide a spring or shockabsorbing suspension of vaparticularly simple and effective character between the inner or bodypart of the wheeland thel rim or tyre-carrying part or parts thereof.

According to the present invention the spring or shock-absorbingsuspension involves a diametrically telescoping annular connectionbetween the body and rim parts of the wheel, in cooperation with aninternal annular series of tension springs connecting said parts anddisposed obliquely and symmetrically in the plane of the wheel andadvantageously in star formation, or in cooperation with an axiallyseparated plurality of such series of tension springs.`

In order that this invention may be clearly understood, and readilycarried .into practice reference may be had to the appended eX-planatory sheet of drawings upon which Figure 1 is a sectional sideelevation of a spring or shock-absorbing wheel according to the presentlinvention. y Figure 2 is a sectional front elevation of the same, on theline Qf-Qof Figure 1.

Figure 3 is a sectional detail view illustratingv the attachment of thetension springs.

Figure 4 is a side elevation, with partsl broken away, of aspring wheelaccording to a modified form of the' invention.

Figure 5 is a sectional front elevation of the saine, on theline 5 5 ofFigure 4l.

In a convenient embodiment of the invention, Figures l to 3, the bodypart a of the wheel may be constructed of aluminium alloy or othersuitable metalin disc.l

formation, or may alternatively be con` structed with spokes, the4 wheelbodyin n either casebeing formed at its inner and enclose between them'a 4circumferential groove a2' of substantialwidth,and` of anlapproximately U-shape or channel shapein cross section. Each of these.flanges a1 is formed with a shallowcannular recessa3 extendingcircumferentially around its yeX- terior face, and within-theserecessesa3 are fittedfa pair of vannular plates b, flush with the inner andouterfaces of the wheel respectively, these plates b forming radial oroutward extensions of `the flanges a1 to thereby provide an enlargementor chambered extension o of the circumferential groove a2 of the wheelbody. The pair of annular plates b are secured firmlyin position ybymeans of a spaced annular series of bolts d passing transversely throughsaid plates and through the flanges al ofthe wheel body a. y y

lBetween the pair of annular plates Z7, and within the chamberedextension 0` of the circumferential groove a2 of the wheel body, isassembled theouter or rim part` e of the wheel. This wheel rime isof achannelor outer faces with flanges at' projecting in the plane ofy thewheel in such a manner asto substantially U-shape inv cross-section,withits parallel inner and outer annular ianges lel indiametrically-telescoping relation to the annular extension plates b ofthe wheel body rlhe rim e carries any suitable, form of tyre or tread faround its base or circumferential part, and is also provided` with aAspaced annular series of bolts all passing through the `flanges" e1 andextending transversely across the interior chamber of the rim at a pointadjacent said circumferentiall base part, these bolts d1 correspondingin number tothe transverse `bolts d. of the wheel body a and beingvlocated in radially7 corresponding positions.

The bolts Z1 of the wheel rim c andthe bolts el of the wheel body a' areconnected,` within the interior annular t-elescoping chamber c of thewheel, by a series of tension springs g in the plane of the wheel.

Each of these vsprings g is of straight spiral formation, and isdisposed obliquely in relation to a radial line of the wheel, that is tosay in a position intermediate between a radial and a tangential line,the vspring being connected at its outer extremity to a bolt d1 of thewheel rim e, and being connected at its inner extremity to a bolt CZ ofthe wheel body a. These obliquely arranged springs g are inclinedalternately in oppo site directions, so that the annular series ofsprings comprise a star formation, so as to be equally effective forrotation of the wheel in either direction.

The attachment of each spring g to the bolt (Z1 and to the bolt Z isadvantageously provided by means of a small eyeletted nipple it, shownin detail in Figure 3, assembled at its eyelet and tl upon the bolt andhaving its enlarged knob end h2 encircled and embraced by the reducedterminal coils gfL of the spring, this construction of spring avoidingany tendency of the spring connection to become detached.

- Advantageously an axially separated pluralit-y of such series oftension springs g in star formation is provided, the number of suchseriesvdepending on the size of the wheel and the width of the internalannulai` chamber c thereof. But the springs of alternate series arearranged in circumferential alternation, that is to say the apicalpoints of the one star forination of springs are connected to alternatebolts d1 of the wheel rim e, and the apical points of the next oradjacent star formation of springs are connected to the intermediatealternate bolts Z1 of the wheel rim e, the spring sus-- pension beingthereby provided at a multiplicity of circumferentially spaced points inthe Wheel. In the drawings vigures l and 2) two such series of tensionsprings g in star formation are illustrated.

In a modified embodiment of the invention, Figures l and 5, as appliedto a wheel of lighter and narrower construction, the obliquely arrangedsprings g are inclined alternately in opposite directions so as tocomprise a single star formation, so that the spring suspension isagainequally eective for rotation of the wheel in either direction.

In the application of the invention to heavy twin-tyred wheels, eachtyre of the pair'is mounted on an independent rim, the pair of rimsbeing arranged side by side in cooper tion with a common intermediateguide plate and a pair of outer guide plates on the wheel body, each rimwith its tyre being connected to the body by an independent series ofthe tension springs, whereby each tyre of the pair can rollowirregularities arising in its respective track, independently of themovement of the other tyre.

Vhat I claim as my invention and desire to secure by Letters Patent isl. A spring wheel comprising a central circular body, a rim, and coiledretractor springs connecting said body and rim, said springs beingarranged tangentially with respect to the body and being also arrangedin cross relation to one another, said body and rim having annulargrooves in their opposing peripheries in which grooves the end aortionsof said s1 rines are arraneed and the said body beingalso provided onopposite sides with plates between which the sides of the rim areguided, bolts passing through the side flanges and plates of the wheelbody and to which the inner ends of said springs are connected and boltspassing through the said flanges of the rim and to which the outer endsof said springs are connected.

2. A wheel comprising a body part having` side flanges projectingoutwardly' in the plane'of the wheel so as to enclose a circumferentialgroove of substantial width and of an approximately U-shaped orchannel-shaped cross section, a pair of annular plates fitted withinshallow annular circumential recesses in the exterior faces of therespective flanges so as to form radial or .outvvard extensions of theflanges and to thereby provide an enlargement or chambered extension ofthe circumferential groove of the body, a rim part of substantantiallyU-shaped or channel shaped cross section having its side flanges indianfietrically telescoping relation to the annular eX- tension platesof the body, a tyre or tread carried by said rim. a spaced inner annularseries of bolts passing through said plates and wheel body Aflanges soas to extend transversely across the -circumferential groove of thebody, a spaced outer annular series of bolts passing through the rimflanges so as to extend transversely across the interior chamber of saidrim, and tension springs obliquely Aconnecting successive pairs of boltsof said inner and outer series. y

In witness whereof I have hereunto set my hand.

FRANCIS BRATT.

